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authorGravatar mike@reedtribe.org <mike@reedtribe.org@2bbb7eff-a529-9590-31e7-b0007b416f81>2012-07-11 01:51:33 +0000
committerGravatar mike@reedtribe.org <mike@reedtribe.org@2bbb7eff-a529-9590-31e7-b0007b416f81>2012-07-11 01:51:33 +0000
commitbad1b2ff1d34ff86693b776f89d7b46995746127 (patch)
treec101051386499f04dfe422ab635d20533eff8d7b /src/utils/SkCullPoints.cpp
parent927ee823fc8789140184ffcf342d434e159413a1 (diff)
add SkPath::contains(x, y)
git-svn-id: http://skia.googlecode.com/svn/trunk@4526 2bbb7eff-a529-9590-31e7-b0007b416f81
Diffstat (limited to 'src/utils/SkCullPoints.cpp')
-rw-r--r--src/utils/SkCullPoints.cpp251
1 files changed, 0 insertions, 251 deletions
diff --git a/src/utils/SkCullPoints.cpp b/src/utils/SkCullPoints.cpp
index a8ec39b042..3e3082f0c0 100644
--- a/src/utils/SkCullPoints.cpp
+++ b/src/utils/SkCullPoints.cpp
@@ -218,254 +218,3 @@ bool SkHitTestPath(const SkPath& path, SkScalar x, SkScalar y, bool hires) {
return SkHitTestPath(path, r, hires);
}
-///////////////////////////////////////////////////////////////////////////////
-
-#include "SkGeometry.h"
-
-static SkScalar eval_cubic_coeff(SkScalar A, SkScalar B, SkScalar C,
- SkScalar D, SkScalar t) {
- return SkScalarMulAdd(SkScalarMulAdd(SkScalarMulAdd(A, t, B), t, C), t, D);
-}
-
-static SkScalar eval_cubic_pts(SkScalar c0, SkScalar c1, SkScalar c2, SkScalar c3,
- SkScalar t) {
- SkScalar A = c3 + 3*(c1 - c2) - c0;
- SkScalar B = 3*(c2 - c1 - c1 + c0);
- SkScalar C = 3*(c1 - c0);
- SkScalar D = c0;
- return eval_cubic_coeff(A, B, C, D, t);
-}
-
-/* Given 4 cubic points (either Xs or Ys), and a target X or Y, compute the
- t value such that cubic(t) = target
- */
-static bool chopMonoCubicAt(SkScalar c0, SkScalar c1, SkScalar c2, SkScalar c3,
- SkScalar target, SkScalar* t) {
-// SkASSERT(c0 <= c1 && c1 <= c2 && c2 <= c3);
- SkASSERT(c0 < target && target < c3);
-
- SkScalar D = c0 - target;
- SkScalar A = c3 + 3*(c1 - c2) - c0;
- SkScalar B = 3*(c2 - c1 - c1 + c0);
- SkScalar C = 3*(c1 - c0);
-
- const SkScalar TOLERANCE = SK_Scalar1 / 4096;
- SkScalar minT = 0;
- SkScalar maxT = SK_Scalar1;
- SkScalar mid;
- int i;
- for (i = 0; i < 16; i++) {
- mid = SkScalarAve(minT, maxT);
- SkScalar delta = eval_cubic_coeff(A, B, C, D, mid);
- if (delta < 0) {
- minT = mid;
- delta = -delta;
- } else {
- maxT = mid;
- }
- if (delta < TOLERANCE) {
- break;
- }
- }
- *t = mid;
- return true;
-}
-
-template <size_t N> static void find_minmax(const SkPoint pts[],
- SkScalar* minPtr, SkScalar* maxPtr) {
- SkScalar min, max;
- min = max = pts[0].fX;
- for (size_t i = 1; i < N; ++i) {
- min = SkMinScalar(min, pts[i].fX);
- max = SkMaxScalar(max, pts[i].fX);
- }
- *minPtr = min;
- *maxPtr = max;
-}
-
-static int winding_mono_cubic(const SkPoint pts[], SkScalar x, SkScalar y) {
- SkPoint storage[4];
-
- int dir = 1;
- if (pts[0].fY > pts[3].fY) {
- storage[0] = pts[3];
- storage[1] = pts[2];
- storage[2] = pts[1];
- storage[3] = pts[0];
- pts = storage;
- dir = -1;
- }
- if (y < pts[0].fY || y >= pts[3].fY) {
- return 0;
- }
-
- // quickreject or quickaccept
- SkScalar min, max;
- find_minmax<4>(pts, &min, &max);
- if (x < min) {
- return 0;
- }
- if (x > max) {
- return dir;
- }
-
- // compute the actual x(t) value
- SkScalar t, xt;
- if (chopMonoCubicAt(pts[0].fY, pts[1].fY, pts[2].fY, pts[3].fY, y, &t)) {
- xt = eval_cubic_pts(pts[0].fX, pts[1].fX, pts[2].fX, pts[3].fX, t);
- } else {
- SkScalar mid = SkScalarAve(pts[0].fY, pts[3].fY);
- xt = y < mid ? pts[0].fX : pts[3].fX;
- }
- return xt < x ? dir : 0;
-}
-
-static int winding_cubic(const SkPoint pts[], SkScalar x, SkScalar y) {
- SkPoint dst[10];
- int n = SkChopCubicAtYExtrema(pts, dst);
- int w = 0;
- for (int i = 0; i <= n; ++i) {
- w += winding_mono_cubic(&dst[i * 3], x, y);
- }
- return w;
-}
-
-static int winding_mono_quad(const SkPoint pts[], SkScalar x, SkScalar y) {
- SkScalar y0 = pts[0].fY;
- SkScalar y2 = pts[2].fY;
-
- int dir = 1;
- if (y0 > y2) {
- SkTSwap(y0, y2);
- dir = -1;
- }
- if (y < y0 || y >= y2) {
- return 0;
- }
-
- // bounds check on X (not required, but maybe faster)
-#if 0
- if (pts[0].fX > x && pts[1].fX > x && pts[2].fX > x) {
- return 0;
- }
-#endif
-
- SkScalar roots[2];
- int n = SkFindUnitQuadRoots(pts[0].fY - 2 * pts[1].fY + pts[2].fY,
- 2 * (pts[1].fY - pts[0].fY),
- pts[0].fY - y,
- roots);
- SkASSERT(n <= 1);
- SkScalar xt;
- if (0 == n) {
- SkScalar mid = SkScalarAve(y0, y2);
- // Need [0] and [2] if dir == 1
- // and [2] and [0] if dir == -1
- xt = y < mid ? pts[1 - dir].fX : pts[dir - 1].fX;
- } else {
- SkScalar t = roots[0];
- SkScalar C = pts[0].fX;
- SkScalar A = pts[2].fX - 2 * pts[1].fX + C;
- SkScalar B = 2 * (pts[1].fX - C);
- xt = SkScalarMulAdd(SkScalarMulAdd(A, t, B), t, C);
- }
- return xt < x ? dir : 0;
-}
-
-static bool is_mono_quad(SkScalar y0, SkScalar y1, SkScalar y2) {
-// return SkScalarSignAsInt(y0 - y1) + SkScalarSignAsInt(y1 - y2) != 0;
- if (y0 == y1) {
- return true;
- }
- if (y0 < y1) {
- return y1 <= y2;
- } else {
- return y1 >= y2;
- }
-}
-
-static int winding_quad(const SkPoint pts[], SkScalar x, SkScalar y) {
- SkPoint dst[5];
- int n = 0;
-
- if (!is_mono_quad(pts[0].fY, pts[1].fY, pts[2].fY)) {
- n = SkChopQuadAtYExtrema(pts, dst);
- pts = dst;
- }
- int w = winding_mono_quad(pts, x, y);
- if (n > 0) {
- w += winding_mono_quad(&pts[2], x, y);
- }
- return w;
-}
-
-static int winding_line(const SkPoint pts[], SkScalar x, SkScalar y) {
- SkScalar x0 = pts[0].fX;
- SkScalar y0 = pts[0].fY;
- SkScalar x1 = pts[1].fX;
- SkScalar y1 = pts[1].fY;
-
- SkScalar dy = y1 - y0;
-
- int dir = 1;
- if (y0 > y1) {
- SkTSwap(y0, y1);
- dir = -1;
- }
- if (y < y0 || y >= y1) {
- return 0;
- }
-
- SkScalar cross = SkScalarMul(x1 - x0, y - pts[0].fY) -
- SkScalarMul(dy, x - pts[0].fX);
-
- if (SkScalarSignAsInt(cross) == dir) {
- dir = 0;
- }
- return dir;
-}
-
-bool SkHitTestPathEx(const SkPath& path, SkScalar x, SkScalar y) {
- bool isInverse = path.isInverseFillType();
- if (path.isEmpty()) {
- return isInverse;
- }
-
- const SkRect& bounds = path.getBounds();
- if (!bounds.contains(x, y)) {
- return isInverse;
- }
-
- SkPath::Iter iter(path, true);
- bool done = false;
- int w = 0;
- do {
- SkPoint pts[4];
- switch (iter.next(pts, false)) {
- case SkPath::kMove_Verb:
- case SkPath::kClose_Verb:
- break;
- case SkPath::kLine_Verb:
- w += winding_line(pts, x, y);
- break;
- case SkPath::kQuad_Verb:
- w += winding_quad(pts, x, y);
- break;
- case SkPath::kCubic_Verb:
- w += winding_cubic(pts, x, y);
- break;
- case SkPath::kDone_Verb:
- done = true;
- break;
- }
- } while (!done);
-
- switch (path.getFillType()) {
- case SkPath::kEvenOdd_FillType:
- case SkPath::kInverseEvenOdd_FillType:
- w &= 1;
- break;
- }
- return SkToBool(w);
-}
-